In one particular type of an optical projection video display system, a two dimensional mirror array is illuminated by a source of optical energy. Under electronic control, the orientation of each of the mirrors is perturbed to determine a propagation path for a beam of light reflecting from each mirror. Each of the reflected beams passes through a slit. The exact path of the reflected beam determines the intensity of optical energy which passes through the slit. The optical energy exiting from the slits is then focused upon a screen. Therefore, the orientation of the mirrors directing each respective one of the reflected beams through the slits determines the intensity for each pixel in the display. Alternatively, the mirror could be vibrated, causing the reflected beam to fan out. The degree of fan out would then be used to control the intensity of light passing through the slits.
Each of the mirrors is controlled by one or more piezoelectric pedestals upon which each mirror is mounted. By applying a DC electrical signal to each of the piezoelectric pedestals, the pedestal shape changes, is as well known in the art, thereby tilting the plane of the reflective surface of the mirror. The amplitude of the DC signal controls the degree of tilting of the mirror. To vibrate the mirror, and AC electrical signal is applied to the pedestal, or pedestals, upon which the mirror is mounted. The amplitude of the AC signal determines the degree of fan out of the reflected beam. Optical projection systems and various configurations of the mirror array have been described in the above referenced applications.